Powerpoint Flashcards
Sinus node rate
60-100
Ectopic atrial pacemaker rate
60-80
Junctional ectopic pacemaker rate
40-60
Ventricular ectopic pacemaker rate
20-40
In a normal sinus rhythm, what is the P wave like in lead II
Upright
In normal sinus rhythm, what is the P wave like in aVR
Inverted
Rhythm in a premature ventricular contraction (PVC)
Irregular
P waves in PVC
Usually not seen
ST segment and T wave in comparison to the QRS complex in PVC
Opposite in polarity (discordant)
QRS complex in PVC
Premature (obviously) and wide
Is there a full compensatory pause in PVC?
Usually
Shockable rhythms
Vtach and vfib
Nonshockable rhythms
Asystole, Pulseless electric activity
Difference b/w defibrillation and synchronous cardioversion
In defib the shock is delivered w/out regards to the cardiac cycle, whereas with cardioversion the shock is delivered when the QRS complex is sensed
Indications for defibrillation
Vfib, pulseless monomorphic vtach, sustained polymorphic vtach
Indications for cardioversion
Unstable afib unstable aflutter unstable momorphic vtach unstable narrow-QRS tachycardia unstable unstable unstable unstable...
Rapid irregular rhythm with chaotic activity and no recognizable P, QRS, ST or T waves
Vfib
Treatment for Vfib
Defibrillation: biphasic, monophasic, AED
CPR for 2 minutes: 30:2 ratio
Epi 1 mg IV every 3-5 minutes or vasopressin 40U (in lieu of 1st or 2nd epi dose
Amiodarone 300 mg IVP (may repeat IV bolus once in 5 minutes @ 150 mg) or lidocaine (if amiodarone not available) 1.5 mg/kg (max 3 mg/kg)
Defib after each step + CPR then recheck rhythm
Signs of unstable cardiac events
Signs of hemodynamic compromise; lightheadedness, SOB, diaphoresis, hypotension, chest discomfort
Treatment for stable monomorphic VT
Amiodarone 150 mg IV over 10 minutes or
Procainamide 20-50 mg/min IV (initially), or
Sotalol 100 mg over 5 minutes
Tx for unstable monomorphic VT
synchronized cardioversion at 100 J
Tx for pulseless monomorphic VT
Same as vfib
Tx for sustained polymorphic VT
Defibrillator
If the is QT prolongation and a nonsustained polymorphic VT, what is the Tx
Mg Sulfate 1-2 g IV
This is torsades de pointes
No rate or rhythm discernible, no QRS complexs, P waves MAY be present (not usually)
Ventricular asystole
Tx for ventricular asystole
Check leads, confirm asystole
Begin CPR
Establish IV access
Epi 1 mg IV every 3-5 min OR vasopressin 40U IV(1 dose to replace 1st or 2nd epi dose)
When do you stop resuscitation
Persistent asystole or agonal EKG pattern despite appropriate ACLS protocol and no reversible cause identified
Tx for PEA
Search for and treat reversible causes and…
Begin CPR
Establish IV access
Epi 1 mg IV repeat 3-5 minutes OR
Vasopressin 40 U (1 dose to replace 1st or 2nd epi dose)
Potentially treatable cause of PEA and asystole (H’s)
Hypovolemia, hypoxia, hydrogen ion (acidosis), hyper/hypokalemia,
hypothermia
Potentially treatable cause of PEA and asystole (T’s)
Tablets (drugs) Tamponade Tension pneumothorax Thrombosis, coronary Thrombosis, pulmonary (embolism)
Sinus tachycardia characteristics
Rate: 101-180
Rhythm: Regular
P waves: Uniform upright in II and always precedes a QRS complex
2 types of pathways in AVNRT
Fast and slow pathways
Describe the fast pathway in AVNRT
Conducts impulse rapidly but has a long refractory period
Describe the slow pathway in AVNRT
Conducts impulses slowly but has a short refractory period
AVNRT characteristics
150-250 BPM, usually 180-200
Ventricular rhythm is regular
P waves often hidden in QRS complex
QRS <.12 seconds
Supraventricular tachycardia (SVT) that starts and ends suddenly
Paroxysmal SVT (PSVT)
Rhythms that originate above the ventricles but the impulse travels via a pathway other than the AV node and bundle of His
AVRT; aka pre-excitation syndrome
3 major forms of pre-excitation syndrome
Wolff-Parkinson White syndrome
Lown-Ganong-Levine (LGL) syndrome
Syndrome that involves the Mahaim fibers
Short PR interval, Wide QRS complex, delta wave
Wolff-Parkinson-White syndrome
Rate in WPW
60-100 usually
PR interval in WPW
.12 seconds or less
QRS complex in WPW
Usually >.12 seconds
Atrial rate in afib; ventricular rate
Atrial rate is 400-600 (no discernible P waves) and ventricular rate is variable
Tx for unstable afib
Cardiovert
Tx for stable afib
Anticoagulate and control rate (BB, nondihydropyridine CCBs, digoxin)
Atrial rate of 250-350 with saw-tooth pattern
Aflutter
Tx for aflutter
Same as afib
Most common wide-QRS tachycardia
VT
Tx for unstable wide-QRS tachycardia
Cardiovert if monomorphic
Defib is polymorphic
Tx for stable wide-QRS tachycardia
If monomorphic AND regular, consider adenosine
Otherwise…
Amiodarone 150 mg IV over 10 minutes or
Procainamide 20-50 mg/min IV (initially), or
Sotalol 100 mg over 5 minutes
If you are giving adenosine for tachycardia, how much do you give for the 1st dose? 2nd dose?
1st: 6 mg rapid IV push follow with NS flush
2nd: 12 mg
Coughing, squatting, breath holding, carotid sinus massage, application of a cold stimulus to the face, Valsalva, and Gagging are all examples of what?
Vagal maneuvers
Rate considered bradycardic?
<60
Tx for symptomatic sinus bradycardia
Atropine .5 mg IV
P wave before each QRS, regular rhythm, prolonged (>.20 s) PR interval
1st-degree AV block
PR interval lengthens each cycle until a P wave appears w/out a QRS
2nd-degree AV block, Type 1 aka Wenchkebach
Every other P wave is followed by a QRS complex
2nd-degree AV block
P wave and QRS complex are completely separate from each other
3rd-degree (Complete) AV block
What do you do if atropine tx for unstable bradycardia is inneffective
Transcutaneous pacing OR
Dopamine infusion OR
Epinephrine infusion
Doses of atropine, dopamine, and epi to give in bradycardia
Atropine: 1st dose .5 mg bolus, repeat every 3-5 min, max 3 mg
Dopamine IV: 2-10 mcg/kg/min
Epi IV: 20 mcg per min
